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Non ADA Gear => Rack Gear => Topic started by: rabidgerry on December 09, 2019, 10:15:29 AM

Title: Boss SX700 - Strange output difference
Post by: rabidgerry on December 09, 2019, 10:15:29 AM
Hello all, seems I only have broken stuff to talk about these days, how frustrating!!  Anyways, I have been using the Boss SX700 for over a year now as my rack effects unit (chorus reverb delay only) and I have to say it's a really good sounding effects unit. It has an analogue thru signal option and allows effects in so many different configurations it confused the hell out of me and was my first introduction to parallel effects.

Anyways the issue is not a big one, but one that bugs me so much that I have very nearly sold the unit and just bought something else.  Alas, playing the unit again over this last week made me think twice as I have just gotten to grips with it and squeezed more quality out of than my initial efforts and I feel it's worth a shot to see what might be the wrong.

Basically one of the outputs (seems to be the left at the minute) is a few db lower than the other side and it could be ignored and I could turn the channel gain up on this side on my multitrack but I have let this issue get to me soooooooo much now I cannot ignore it.

Things I have tried:

swapping cables,
checking other channels on my multitrack in case it was an issue at that side,
taken the unit out altogether leaving my preamp solely into my Intellipitch to see if the anomaly is there,
checking the speaker impulse in case it isn't balanced,
checking the patch outputs are equal on left and right side,

and basically my conclusion is, there is a few db difference between channels on the outputs and I really do not understand why this would be.

Anyone any ideas on what I could do or check or fix the issue I would be very grateful.


Thanks

Gerry
Title: Re: Boss SX700 - Strange output difference
Post by: rnolan on December 10, 2019, 12:09:28 AM
Hey RG, Not to be a d*ck but have you cleaned the jack sockets? I assume you have but you didn't mention it....  Is there any balance settings in the unit?  or it could be the way various FX are sending/receiving e.g. this fx out to that fx in etc and even their operation e.g. L is dry signal, R is wet.
Title: Re: Boss SX700 - Strange output difference
Post by: vansinn on December 10, 2019, 08:56:01 AM
To make sure which side is really the few DB lower, try swapping both inputs and outputs from left to right, that is, left out to right next-device and visa versa. Do inputs and outputs separately and check between each step.
The problem should follow the swapped direction and now manifest itself on that side.

When you've made sure which channel is the culprit, as Nolan says, try cleaning the sockets.
If this doesn't help, open it up, inspect, and if nothing seems obvious, try locating which opamps sits in the signal chain.
If those are in sockets try pulling and reinsert them a couple times; chances are there could be corroded contacts.
If this doesn't help, try re-soldering first input and jacks, and if still no luck, then re-solder the whole circuit board.

Do you know if there are programmable analog potmeter IC's in the signal chain?
If so, those too could be either partially defunct or have a socket/solder problem.

Disclaimer: I have no experience with the SX700, and never seen the schematics.
Title: Re: Boss SX700 - Strange output difference
Post by: rabidgerry on December 10, 2019, 12:15:49 PM
I will find out which channel it is for sure.

There is no balance controls as such, there is a left and right output and they are both evenly set.  Also in bypass the output difference is there.  As I mentioned also it isn't a lot but it's enough to piss me off.

No I have not cleaned the jack outs, but I will.  It definitely seems to be at the out put stage as the input stage seems fine coming from the piece of gear before the boss which is the rocktron intellipitch.


I will clean first guys and report back.
Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 10, 2019, 03:25:31 PM
Hello Gerry! Has the SX700 always done this? Or is this a new issue?
Title: Re: Boss SX700 - Strange output difference
Post by: rabidgerry on December 11, 2019, 10:18:32 AM
I am going to say it may have always done it, but I put up with it for so long as it's not massively noticeable and it's easy to let slide once you get used to it.  I originally thought it was the headphones I was using and that they were damaged.  But I tested them and they were fine else where.  I also used to adjust the input gain on my multitrack to compensate so another reason I forgot the issue was there.
Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 11, 2019, 10:48:57 AM
Yeah, that's what I was afraid of. My Boss GT 100 does basically the same thing. Boss in their infinite wisdom has one side full wet 100%, the other side isnt. Its I'm guessing maybe 75% wet. Something to do with the delays dry vs wet. With no means of adjusting it. That is where the difference in db's is. It's not much but still noticable. It doesnt matter if I use the Stereo chorus, stereo delay or the stereo reverbs on or bypassed, same issue results. You can minimize it by turning the stereo chorus level to 100% but that tone isnt always ideal. I compensate by turning up the monitor a touch on the low side. Not a fix but a useable work around. That's just the nature of the beast my friend.
Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 11, 2019, 11:29:22 AM
Ok I found my explanation from Roland/Boss USA. "Some stereo effects such as chorus, delay and reverb will sound drier on one side even if not running in stereo. This will result in slightly lower output on one side. Compensate by panning more towards the drier side."
This is probably the same issue you are experiencing.
Title: Re: Boss SX700 - Strange output difference
Post by: rabidgerry on December 11, 2019, 01:12:40 PM
That's all quite interesting and I wonder did I experience this with my old GT6 and GT8???  I don't think my GT5 does it.

Ok what I'm confused at is the fact that when I bypass it's actually more noticeable.

And yeah cleaning the outputs did shit all.

How I would describe the difference (I'm seem to be super sensitive to the slightest nuance of difference with these things for some God unknown reason) is that it sounds like a tad more low end on the louder side.

Also the channel that is the lower channel is definitely the Right channel.  I had the leads around the wrong way after switching and testing different cables.

I don't get this one side is wetter than the other.  Now on the SX700 there are silly amount of mixer levels and options.  The master output option to mix dry and wet isn't even needed simply because you can mix dry and wet within the main mixer and there is no need for a master option to do the same thing globally.

However if what you say is true it can really solve my issue simply by reducing ether the left global wet/dry control to say 75% to balance out the difference or boosting the right (both of which are possible with the SX700).  I might try this as opposed to balance out using the gain knobs on my multitrack.

What's cool about the SX700 is a "thru" option which allows an analogue signal to be passed through untouched, so I usually makes the effects full wet then use their outputs to mix them into the thru signal.  Also I can have some effects in parallel with one another.  Having chorus in parallel to reverb gives a really clean separation between the two effects so when the finally get blended together at the output stage they sound really cool.  Almost like its being multitracked or something. However I like using the series mode too but the mixer section is tricky to get your head around to get that to work, too many options really.

Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 11, 2019, 02:18:33 PM
Right side being lower makes sense, mine is the same. Left is mono then you add the right for stereo. Their assumption is most people will run mono, stereo in their eyes is for a fuller chorus and delay repeats. So in my eyes that's not true stereo. More like a pseudo stereo.
I have no wet/dry mix to adjust. I have a stereo spread adjustment but anything shy of center sounds very distant almost like in a tunnel. Totally useless!
I can create dual signal chains amps and all totally identical and still quieter on the right. Other than that the thing sounds amazing. Let me know how it goes :thumb-up:
Title: Re: Boss SX700 - Strange output difference
Post by: rabidgerry on December 12, 2019, 10:05:19 AM
Now I'm gonna go out on a limb here and say that the  SX700 is definitely stereo from start to finish.  I could be wrong, but I know if I send two separate signal left and right input I still hear those in the left and right channel.  I suppose my unit is a different beast albeit a lot older.  It's not even specifically for guitar either.  Also I'm pretty sure the manual has diagrams showing the signal path.  I may have imagined this.

Ok so on those wet controls and using my meters on my multitrack as guidance, I didn't really feel like I was fixing the issue by adding more to the right output.  I bumped it right up to like 180% at one point whilst left was at 100% and it only then seemed to be balancing out.  I guess it seemed ok a bit in and around 125% 130% but I dunno.  I wasn't convinced what I was doing was balancing out in regards to wet and dry.  Like it doesn't seem like a wet and dry issue to me either.  It seems like solely output.  I say this as bypassed is the same.  It's actually less noticeable with stereo effects on.

Not sure if I can live with this despite the unit sounding fantastic.  I'm really  :crazy: about stuff like that.
Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 12, 2019, 10:27:23 AM
Definitely an output issue as with mine also. However according to the manufacturer mine is designed that way. They never explained why those effects are quieter on one side. So by turning up the volume out on my right monitor from say 5 to 5 1/2  leaving the left at 5 balances it out. So that is what I've been doing. I cant adjust the GT100 that way but I can adjust my monitors that way, then when I go xlr out of each monitor to foh it's all even, full and spacious....mmmmm wet guitar!  If you like the tones you are getting from the SX700 you will find a work around. I know it ain't perfect but for your grail tone sometimes we need to overlook certian short comings of gear, adapt and overcome! :metal:
Title: Re: Boss SX700 - Strange output difference
Post by: Soloist on December 13, 2019, 12:18:42 PM
I found a great fix for mine, maybe this will work on yours as well. I've been tinkering around with mine again since your post, here's what I found. In the settings under chorus, reverb  whatever I have a direct mix control for each stereo effect. If I drop it from 100 to 75 both right and left volume are now the same db level. :headbanger: If I change that in my reverb which is the last effect in my chain it does lower the overall volume of the preset a bit so I just increase the patch volume. You only need to adjust any one of those effects and instant true stereo!
Title: Re: Boss SX700 - Strange output difference
Post by: vansinn on December 14, 2019, 11:26:34 AM
Well, that sounds strange to me.  If these parameters controls some analog gain-regulating devices, these might be in not fully correct working order.
If these controls are all digital, it's out of my league ;)

Oh well, you found a fix..
Title: Re: Boss SX700 - Strange output difference
Post by: rabidgerry on December 15, 2019, 03:11:56 AM
Well I know with the sx700 there is no way of turning the analogue thru down or up, it's whatever level you have going into the unit.  Then you blend your digital effects in with this signal.  You can use the digital dry signal if you wish but I currently do not although that does have the flexibility of lowering its level directly, where as the "Thru" is either on or off.